A 20 residue long amino acid sequence needs to be designed that results in the amphipathic alpha-helical secondary structure. Concept Introduction : The AH or membrane-binding amphipathic helix is a communal motif encountered in numerous peptides and proteins. Amphipathicity resembles to the separation of polar and hydrophobic residues between the two opposite faces of the a-helix, a distribution designed for the membrane binding.

Question

Remembering that the amino acid side chains projecting from each polypeptide backbone in a β sheet point alternately above and below the plane of the sheet, consider the following protein sequence: Leu-Lys-Val-Asp-Ile-Ser-Leu-Arg- Leu-Lys-Ile-Arg-Phe-Glu. Do you find anything remarkable about the arrangement of the amino acids in this sequence when incorporated into a β sheet? Can you make any predictions as to how the β sheet might be arranged in a protein?

Answer 1

Question

Chapter 31, Problem 20P

Interpretation Introduction

Interpretation:

A 20 residue long amino acid sequence needs to be designed that results in the amphipathic alpha-helical secondary structure.

Concept Introduction :

The AH or membrane-binding amphipathic helix is a communal motif encountered in numerous peptides and proteins. Amphipathicity resembles to the separation of polar and hydrophobic residues between the two opposite faces of the a-helix, a distribution designed for the membrane binding.

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